Chest pain during the day and no pain at night may be caused by a variety of reasons such as strenuous exercise, costochondritis, pleurisy and so on. 1. Strenuous exercise: some patients do strenuous exercise during the day, which may cause the body to be in a state of overwork, causing chest pain during the day, and after a period of rest, no chest pain at night. 2. Costal chondritis: prolonged engagement in heavy physical labor or cold air stimulation will cause costal chondritis disease. When the inflammation continues to stimulate, it may also cause chest pain during the day and no pain at night. 3. Pleurisy: Bacterial infection in the pleural area can easily cause inflammatory diseases. If not treated in time, the inflammation may also affect the surrounding tissues, causing the patient to experience chest pain during the day, and after sleeping at night, the pain symptoms will be alleviated during sleep, and there will be no pain at night. Chest pain during the day and no pain at night may also be caused by other causes, the patient should go to the hospital in time to receive treatment to help relieve the symptoms.